A gas detection system, which comprises a central unit and a plurality of measuring devices on the site, which are connected to the central unit, has been known from DE 38 19 128 C2. Various types of measuring devices may be interchangeably inserted into the measuring devices, and the gas sensors are provided in the base area with an identification system in the form of soldered contact bridges in order for the measuring device to recognize the gas sensor that has been inserted. The prior-art identification system requires a plug in the connection area between the measuring device and the gas sensor with a plurality of plug-type contacts in order to transmit the sensor information in the binary coded form to the measuring device. Such multiple-contact plugs are expensive, on the one hand, and, on the other hand, the fault liability or fault susceptibility increases with increasing number of plug-type contacts. In addition, there is only a limited possibility of retrofitting existing measuring devices for new sensor applications, because the originally designed plug coding must be retained for reasons of compatibility.